Professor G. S. Mehmi

Motion of heat energy from one body to another body or from one part of a body to another part of body is called the transfer of heat. There are three modes of transfer of heat: (i) Conduction (ii) Convection (iii) Radiation (i) Conduction:  The process of transfer of heat in a material medium in which heat energy is transferred from molecule to molecule in the direction of fall of temperature without the actual motion of the molecules of the medium is called conduction. (ii) Convection: The process of transfer of heat in which heat is transferred from one point to another point by the actual motion of the heated particles away from the source of heat is called convection. (iii) Radiation: It is the process of heat transfer in which heat is transferred from one place to another place in straight lines, in the form of heat waves with the velocity of light without heating the medium through which it passes.  For e.g. Heat from the sun comes to us on the earth by radiation. ...

Heat : 1. Heat is the total kinetic energy possessed by all the molecules of a substance. 2. Heat energy depends on the speed of the particles, the number of particles, size and type of particles. 3. Heat is the cause, temperature is the effect. By adding or removing heat from a substance, its temperature can be increased or decreased. For e.g. As we add heat to a substance its temperature increases and if we remove heat from a substance its temperature decreases. 4. Heat is a form of energy. 5. SI unit of heat is joule. Temperature : 1. Temperature is the measurement of average kinetic energy of all the malecules of a substance. 2. Temperature of the substance does not depend on the size or type of particles of the object. 3. Temperature is the effect however with addition or remove of heat from substance, temperature of the substance changes. But heat will always flow from a  body at higher temperature to a body at lower temperature. 4. Temperature is not energy but a m...